It is argued that an understanding of the attentional processes which influence the selection of "effective" stimuli from the array of "available" stimuli is important for theories of person perception. Research is proposed which applies to the perception of self and others attentional concepts and data which have been generated in research on object and speech perception. Four determinants of attentional allocation will be investigated: arousal, sex, and weight of the perceiver, and the discriminability of available stimuli. The effects of these variables on attentional span and selection will be ascertained from several indices of attention. These will include visual fixation, neurophysiological habituation, causal attributions for a stimulus person's behavior, recall of the behavior, self-perceptions of emotion, effort, and location, and the effects upon performance of distracting vs. facilitating cues.